Evening primrose oil
Oenothera biennis
Supplements. Western & European and Native American.
Also called Evening primrose, EPO, Common evening primrose
Spanish: Onagra
May lower seizure thresholdAn oil pressed from the seeds of a yellow wildflower, rich in gamma-linolenic acid (GLA), an omega-6 fat.
Did you know? The flowers open quickly at dusk and fade by the next morning, which is how the plant earned its name.
What it may help, and how strong the proof is
- Women's health. Used for breast pain and PMS. Some small trials show less breast pain than placebo, but other trials found no clear difference.Early proof
- Skin. Sold for eczema. Reviews of oral oil found no clear benefit over placebo, so this claim is not supported.Not supported
Parts of the body
Traditional use
Native American peoples ate the roots and used the plant on bruises and skin injuries. Modern oil products are a much newer development.
How it is classified
- Herbal actions
- Anti-inflammatory, Nutritive. Energy: neutral.
How people take it
Capsules often contain 500 to 1,000 mg. Trials have used a wide range of doses, and no dose has been shown to work best.
Capsule and oil.
Where to get it
The oil is pressed from the seeds of cultivated evening primrose, grown in Europe, Asia, and North America. Many brands add vitamin E to slow spoilage.
Be careful
Common side effects are stomach upset, loose stools, headache, and bloating. It may lower the seizure threshold, so avoid it if you have epilepsy. Avoid it in pregnancy, because it may affect uterine activity and labor.
Avoid if: pregnancy; epilepsy; bleeding disorders.
Mixing with other things
- Works well together
Both are GLA-rich seed oils that are often compared and sold side by side.
- Works well together
Vitamin E protects the oil from spoiling and is often added to products.
- Use cautionBlood thinners (warfarin, Eliquis, Xarelto, Plavix, daily aspirin)
May add to bleeding risk with blood thinners. Report easy bruising or bleeding to your doctor.
Adds up with others that may slow blood clotting: , , , , , , , , , , , , , and 40 more.
The honest take
The eczema claim is the clearest case: reviews could not show that the oil helps. Breast pain results are mixed, and most other claims are unproven. The oil is a fat supplement, not a proven remedy for hormone or skin problems.